1. Technical Field
The present invention relates to a system and method that controls access to peripheral devices. More particularly, the present invention relates to a system and method that shares a secret between the peripheral device and a computer system to protect usage of the peripheral device.
2. Description of the Related Art
Computer virtualization software is an increasingly popular method of running multiple operating systems on a single computer system. There are many benefits of virtualization. These benefits include allowing an organization to consolidate computer systems (e.g. servers) and increase the scale of the server infrastructure without having to purchase additional hardware. Reducing the number of physical computer system machines that an organization needs leads to improved energy conservation and may lower an organization's utility bills. Virtualization also improves the management of machines as it is generally easier to manage one physical machine that is hosting multiple operating systems instead of multiple physical machines, each hosting a different operating system. Backup and recovery times can also be reduced in a virtualized environment. Virtualization also aids in testing software configurations, maintaining legacy software applications, and reducing the amount of physical space needed to house the organization's physical computer systems. While virtualization provides many benefits, it also presents new challenges to the organization, especially with regard to firmware and device driver updates.
Computer peripheral devices utilize firmware to operate. For example, a DVD-player uses firmware stored in its Read-Only-Memory (ROM) to read a CD or DVD. To access devices under an operating system, such as Microsoft Windows™ or Linux™, software called a device driver” is used to use (control) the device. The device driver is installed in the operating system and includes instructions that allow the operating system to use and control the device. Using the DVD-player example, the device driver allows the operating system to control the DVD-player in order to play a movie or write/read files from/to the device. From time-to-time the firmware and device drivers for a device may need to be updated for a variety of reasons, such as correcting a bug in the firmware or device driver, improving the efficiency or use of the device, addressing a security vulnerability discovered with the device, or many other reasons.
One challenge in virtualization is managing these device drivers and firmware. This challenge is due to the fact that, when using virtualization software, the operating systems do not access the physical hardware and therefore do not readily recognize when updates to the device driver or firmware are needed. Traditional methods of updating firmware and/or a device driver often require a re-boot or a shutdown of the computer system before the update becomes effective. Because multiple operating systems run on a common computer system in a virtualized environment, a shutdown or re-boot of the computer system impacts each of the operating systems that is being hosted. This is another challenge encountered when managing a virtualized computing environment.